Method of polymerizing glycerin



' mers after nitration. I have found,

use in the manufacture of exp Patented Sept. l1, 1923.

. UNITED STATES PATE'NT OFFICE.

RAYMOND I. BASHFORD, OF CLEVELAND HEIGHTS, OHIO, ASSIGNOR TO THE GRASSELLI I POWDER COMPANY, OF CLEVELAND, OHIO, A CORPORATION OF OHIO.

METHOD OF POLYMEBIZINO- GLYOERIN.

F0 Drawing.

To all whom it may concern:

Be it known that I, RAYMOND I. BASH- ronn, a citizen of the United States, and a resident of Cleveland Heights, county of Cuyahoga, and State of Ohio, have invented a new and useful Improvement in Methods of Polymerizing Glycerin, of which the following is a specification, the principle of the invention being herein explained and the best mode in which I have contemplated applying that principle, 50 as to distlnguish it from other inventions.

The present invention relates to an improved method of polymerizing glycerin for osives. It has long been known that polymerizedsor condensed glycerin can be nitrated and in this way made to stand very much lower temperatures than ordinary nitro-glycerlnwithout freezing and various methods have been attempted for polymerizing the glycerin before nitrating in order to make a low freezing explosive. The present invention affords a simple and inexpensive method of thus treating glycerin.

My invention, then, consists of the steps hereinafter fully described and particularly pointed out in the claims, the following description setting forth in detail certain steps embodying the invention, such disclosed steps constituting, however, but one of the various ways in which the principle of the invention may be used.

It has been known that the use of alkalies in connection with glycerin exerts a condensing or polymerizing efiect, but that these have not been used extensively because of a the formation of objectionable higher polyowever, that if glycerin be treated with zinc chloride in relatively small amounts, this chloride acts as a catalytic agent and assists in a speedy polymerization of the glycerin which is then in a condition that is easy to handle in the subsequent steps of manufacture and is'entirely stable. A glycerin so polymerized after nitration has an extremely low freezing point, and further, is very slow to freeze at these lower tempera tures. I

The polymerizing of glycerin by my improved method consists in heating a suitable quantity of glycerin at a temperature of be- I Application filed 0ctober 17, 1921. Serial No. 508,219.

tween 220 and 260 degrees centigrade for a period of several hours with the addition of a minute quantity of zinc chloride. I have found that very satisfactory results are obtained by continuing the heating for a period of about five hours, at a temperature ranging between 240 and 250 degrees centigrade, with one-half of one per cent of zinc chloride added to the glycerin. Larger amounts of zinc chloride have no injurious eflect but do not increase the speed of polymerizing to any appreciable extent. If desired, the action may be carried on under reduced pressure which shortens the time necessary for complete polymerization.

Other chlorides than zinc exert a similar I as will also various other metallic chlorides.

Other modes of applying the principle of my invention may be employed instead of the one explained, change being made as regards the mechanism herein disclosed, provided the means stated by any of the following claims or the equivalent of such stated means be employed.

I therefore particularly point out and distinctl claim as my invention 1. n a method of polymerizing gl cerin, the steps which consist in treating g ycerin with a metallic chloride.

2. In a method of pol erizing glycerin, the steps which consist in treating glycerin with zinc chloride.

3. In a method of polymerizing glycerin,

at a temperature above 230 degrees centigrade with a metallic chloride.

4. In a method of polymerizing glycerin,

the steps which consist in heating glycerin with less than one per cent of a metallic chloride.

5. In a method of polymerizing glycerin,

the steps which consist in heating glycerin at a temperature of about 250 degrees centi- Signed by me, this 8 day of October, 1921.

RAYMOND I. BASHFORD. 

